Google Calendar How to get Date Object

Question

I'm trying to display the events of a google calendar using the google calendar API in java. But I don't have any idea on how to get the date (and time) of my events in a nice looking format. The only thing I can do is the following:

DateTime now = new DateTime(System.currentTimeMillis());
Events events = service.events().list("primary")
        .setMaxResults(7)
        .setTimeMin(now)
        .setOrderBy("startTime")
        .setSingleEvents(true)
        .execute();
items = events.getItems();


items.get(0).getStart().getDateTime();

which leads to the following output: 2018-11-06T18:00:00.000+01:00

Any idea on how to get it eg as a Date Object?

Answer 1

According to the Google API reference the type DateTime has a method getValue() which

Returns the date/time value expressed as the number of milliseconds since the Unix epoch.

To get an java.util.Date we can use this long value:

Date date = new Date(items.get(0).getStart().getDateTime().getValue());

But note that since Java 8 there is the java.time API. To get a LocalDateTime you can go on like that:

ZoneOffset offset = ZoneOffset.ofTotalSeconds(items.get(0).getStart().getDateTime().getTimeZoneShift() * 60);
ZoneId zone = ZoneId.ofOffset("UTC", offset);    
Instant instant = date.toInstant();
LocalDateTime dateTime = LocalDateTime.ofInstant(instant, zone);

To determine the appropriate ZoneId we use the method getTimeZoneShift() which

Returns the time zone shift from UTC in minutes or 0 for date-only value.

Since ZoneId.ofOffset takes as second parameter a value in seconds, we have to convert the minutes returned by getTimeZoneShift() to seconds first.